I think it was RAAM built a 440 and set the quench pretty loose like around .080 or something then tightened it up to like .040 or so and saw a dramatic increase in power as RPM went up, something like 80hp. It was quite a bit more hp than the compression alone should have accounted for. Maybe someone can find a link to his post, I think it was a 440 he built for towing so we can look at the details again.